Bioterror CSIs Target Germs

Randy Dotinga
03.15.05

SAN DIEGO -- Back in 1346, it didn't take a CSI unit to uncover the culprits behind one of history's first cases of bioterrorism. Nobody could miss the plague-ridden corpses and heads catapulted over the walls of the ancient city of Kaffa, under siege by the Tartar army.

Nor could Kaffa residents ignore the subsequent epidemic, which led to their surrender and may have set off the Black Death.

Nearly seven centuries later, it's easier to secretly spread deadly germs around and harder to figure out who did it. But pioneers in the emerging field of bioterrorism forensics hope to change that equation by exposing the secrets lurking in the DNA of bioweapons.

"It's not enough to detect (a bioagent). You have to be able to attribute who made it, how they made it, what materials have gone into it," said Barbara Seiders, manager of chemical and biological defense programs at the Pacific Northwest National Laboratory in Richland, Washington.

An anthrax germ, for example, might reveal signs of the laboratory where it was created. A plague bacterium could indicate the kind of solution used to raise it. And, at least in the dreams of scientists, the genetic makeup of ricin could help identity the single castor bean plant that produced it.

On Monday at the American Chemical Society's annual meeting in San Diego, scientists discussed a variety of forensic tools, from advanced mass spectrometry, which identifies the components of a material, to the chemical analysis of water, which could identify the region of the country where a germ was grown by providing an aquatic fingerprint.

But there are plenty of limitations.

"We've got a lot of questions to answer, and we're fairly limited in what we can say right now," said Randall Murch, former deputy director of the FBI Laboratory and now associate director of research-program development at Virginia Tech, at the meeting.

After all, the field of American bioterrorism forensics is barely a decade old. It's a product of terrorism fears at the 1996 Olympics in Atlanta -- and a full 10 to 20 years behind the advanced world of civilian criminal forensics, said Murch in an interview. Obscure threats, like the disease tularemia, remain largely unexamined, and researchers must poke through a bounty of potential germ clues to figure out which ones hold meaning.

Then there's the uninspiring matter of the ongoing investigation of the 2001 anthrax attacks. Scientists managed to identify the strain of anthrax used, but the case remains unsolved.

"It was clear that even though we knew what the strain was, we came to understand that scientists had been exchanging it all over the world," Seiders said. "Trying to track it only knowing the strain wasn't enough."

Finding a suspect with anthrax in his basement laboratory wouldn't have been sufficient either.